{"id":"CVE-2025-39721","summary":"crypto: qat - flush misc workqueue during device shutdown","details":"In the Linux kernel, the following vulnerability has been resolved:\n\ncrypto: qat - flush misc workqueue during device shutdown\n\nRepeated loading and unloading of a device specific QAT driver, for\nexample qat_4xxx, in a tight loop can lead to a crash due to a\nuse-after-free scenario. This occurs when a power management (PM)\ninterrupt triggers just before the device-specific driver (e.g.,\nqat_4xxx.ko) is unloaded, while the core driver (intel_qat.ko) remains\nloaded.\n\nSince the driver uses a shared workqueue (`qat_misc_wq`) across all\ndevices and owned by intel_qat.ko, a deferred routine from the\ndevice-specific driver may still be pending in the queue. If this\nroutine executes after the driver is unloaded, it can dereference freed\nmemory, resulting in a page fault and kernel crash like the following:\n\n    BUG: unable to handle page fault for address: ffa000002e50a01c\n    #PF: supervisor read access in kernel mode\n    RIP: 0010:pm_bh_handler+0x1d2/0x250 [intel_qat]\n    Call Trace:\n      pm_bh_handler+0x1d2/0x250 [intel_qat]\n      process_one_work+0x171/0x340\n      worker_thread+0x277/0x3a0\n      kthread+0xf0/0x120\n      ret_from_fork+0x2d/0x50\n\nTo prevent this, flush the misc workqueue during device shutdown to\nensure that all pending work items are completed before the driver is\nunloaded.\n\nNote: This approach may slightly increase shutdown latency if the\nworkqueue contains jobs from other devices, but it ensures correctness\nand stability.","modified":"2026-04-16T04:36:56.201963784Z","published":"2025-09-05T17:21:28.911Z","related":["SUSE-SU-2025:03600-1","SUSE-SU-2025:03634-1","SUSE-SU-2025:20851-1","SUSE-SU-2025:20861-1","SUSE-SU-2025:20870-1","SUSE-SU-2025:20898-1","SUSE-SU-2025:21074-1","SUSE-SU-2025:21139-1","SUSE-SU-2025:21179-1","SUSE-SU-2025:3751-1","SUSE-SU-2025:4057-1","SUSE-SU-2025:4132-1","SUSE-SU-2025:4141-1","openSUSE-SU-2025:20081-1"],"database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/39xxx/CVE-2025-39721.json","cna_assigner":"Linux"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/3d4df408ba9bad2b205c7fb8afc1836a6a4ca88a"},{"type":"WEB","url":"https://git.kernel.org/stable/c/5858448a6c65d8ee3f8600570d3ce19febcb33be"},{"type":"WEB","url":"https://git.kernel.org/stable/c/e59a52e429e13df3feb34f4853a8e36d121ed937"},{"type":"WEB","url":"https://git.kernel.org/stable/c/fa4c14a82747886d333d8baef0d26da86ba1ccf7"},{"type":"WEB","url":"https://git.kernel.org/stable/c/fe546f5c50fc474daca6bee72caa7ab68a74c33d"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/39xxx/CVE-2025-39721.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2025-39721"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"e5745f34113b758b45d134dec04a7df94dc67131"},{"fixed":"fa4c14a82747886d333d8baef0d26da86ba1ccf7"},{"fixed":"5858448a6c65d8ee3f8600570d3ce19febcb33be"},{"fixed":"fe546f5c50fc474daca6bee72caa7ab68a74c33d"},{"fixed":"e59a52e429e13df3feb34f4853a8e36d121ed937"},{"fixed":"3d4df408ba9bad2b205c7fb8afc1836a6a4ca88a"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2025-39721.json"}}],"schema_version":"1.7.5"}